1. Field of Invention
This invention is directed to an ultrasound multiphase meter and method to detect and quantify the phase fractions and flow rates in a multiphase flow stream.
2. Description of the Related Art
Multiphase meters have attracted the attention of the oil production industry because of their accuracy and cost savings as opposed to analyzing discrete samples of multiphase fluid to determine fractions of oil, water, and gas. Development of accurate and compact multiphase metering devices that can be installed at well heads in remote onshore fields and unmanned offshore platforms continues to be a technological challenge. Data acquired by such devices may be used in reservoir management and production allocation inasmuch as the particular volumetric fractions of oil, water, and gas can be determined. Therefore this data is highly valuable. However, conventional devices have had difficulty in producing an accurate measurement of various properties of the monitored multiphase while withstanding the harsh environments in which such devices are typically installed.
Multiple array ultrasound devices that may acquire real time spatial data from volumetric specimens have been developed for medical applications. Advanced data and signal processing systems and display technologies have been developed for aerospace and the defense industries. These technologies are unsuitable to quantify phase fractions and flow rates of oil, gas, and water in a multiphase flow stream in an oil pipeline. In particular, the field conditions of the oil production environment are extremely harsh because of high pressure and temperatures and because of abrasive particles such as sand. Furthermore, the presence of gas bubbles in the flow streams as well as effects due to high temperature and pressure in the pipeline require specialized models to obtain accurate data collection and analysis.